1. Field of the Invention
The present invention relates to a semiconductor light receiving device, an optical receiver module, and manufacturing methods thereof.
2. Description of the Related Art
There is known a semiconductor light receiving device having a mesa structure buried by a buried layer. With the mesa structure buried by the buried layer, the reliability of the device is improved. For example, in JP 2008-270529 A and JP 2010-278406 A, there are disclosed back-illuminated avalanche photodiodes. In the back-illuminated avalanche photodiode disclosed in JP 2008-270529 A, a first mesa 110 including a p-type InGaAs light-absorbing layer 106 and a p-type InAlGaAs cap layer 107 is formed, and the first mesa 110 is buried by a buried layer 111 formed of a p-type InP crystal. Further, in the back-illuminated avalanche photodiode disclosed in JP 2010-278406 A, a first mesa structure 208 including a p-type InAlAs electric field adjusting layer 204c, a p-type InGaAs light-absorbing layer 205, a p-type InAlGaAs cap layer 206, and a p-type InGaAs contact layer 207 is formed, and the first mesa structure 208 is buried by a buried layer 209 formed of a Fe-doped InP crystal.